cf.asm

学习单片机一个简单程序和硬件的开发

	ORG 0000H
	AJMP MAIN
	ORG 0030H
MAIN:
	MOV R4,#04H
LOOP:
	MOV @R0,#00H
	INC R0
	DJNZ R4,LOOP ;结果单元清零
	DEC R0
	ACALL BMUL
	SJMP $
BMUL:
	MOV A,R3
	MOV B,R7
	MUL AB		 ;低字节相乘
	ACALL RADD
	MOV A,R2
	MOV B,R7
	MUL AB		 ;高低字节交叉相乘
	INC R0
	ACALL RADD
	MOV A,R3
	MOV B,R6
	MUL AB		 ;高低字节交叉相乘
	INC R0
	INC R0
	ACALL RADD
	MOV A,R2
	MOV B,R6
	MUL AB		 ;高字节相乘
	INC R0
	ACALL RADD
	RET
RADD:			 ;计算结果累加子程序
	ADD A,@R0
	MOV @R0,A
	MOV A,B
	DEC R0
	ADDC A,@R0
	MOV @R0,A
	DEC R0
	MOV A,@R0
	ADDC A,#00H
	MOV @R0,A
	RET
	END